MADREPORARIA OF THE DEEP SEA. 321 
fourth, which are usually rudimentary, are absent. The primary and the secondary 
septa are nearly equal in size, and are large, projecting, exsert, thin, and marked with 
distinct granules. ‘The secondary septa are not so high as the primary. ‘The tertiary 
septa are smaller and less exsert than those already mentioned, and they usually unite 
to the secondary near the false columella. 
The columella is formed by processes from the ends of the larger septa. 
The interseptal spaces are broad and shallow. 
The cost are more numerous than the septa. The primary and secondary cost are 
slightly prominent at the calicular margin, and may be traced to the fine peduncle. 
The third and fourth orders are less so; and there are some traces of a fifth cycle in 
the form of wavy rows of granules or ridges. 
The height of the corallum is 3; inch; and the breadth of the calice is 345 inch. 
Dredged up in No, 16 dredging, second expedition of the ‘Porcupine, and in 
994 fathoms. 
I have named this new Turbinolian genus after Sir Edward Sabine, K.C.B., the 
President of the Royal Society. 
Genus DesmMopHyLLuM, Ehrenberg. 
DESMOPHYLLUM cRISTA-GALLI, Milne-Edwards and Jules Haime, 1848, op. cit. (Plate 
XLI. figs. 10-16.) 
Desmophyllum dianthus, Ehrenb. 1834. 
a. —— cumingi, Milne-Edwards & Jules Haime, 1848, op. cit. 
B. costatum, Milne-Edwards & Jules Haime, 1848, op. cit. 
If the variations of the typical form of this species are studied, it will be noticed that 
there are great differences in the position, size, and continuance of the costae, in the 
exsertness and granulation of the septa, in the height, compressedness, and size of the 
base of the corallum, and in the granular ornamentation of the outside of the wall in 
different specimens. The recognition as varieties of the forms marked « and #, instead 
of species, is necessary. 
The size, costal development, exsertness, and granular condition of the ornamentation 
of the septa and outside of the corallum depend upon the age and nutrition of the 
specimen. Very thin septa are not so granular superiorly as those of corallites which 
have very dense walls and thick septa; and the cost of the latter kind are usually 
most prominent. 
At great depths, 994 fathoms, No. 16 dredging ; and where the Madreporaria appear to 
be very abundant the specimens of Desmophyllum are usually very granular externally ; 
moreover they become attached to compound forms of corals, and both have the same 
ornamentation, so that it is difficult not to believe in the Desmophyllum being part and 
parcel of the growing mass. They are especially liable to be joined to branches of the 
fistulose bifurcating coral which will be described further on (Solenosmilia variabilis). 
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